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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 3 |
| 5 | 9 |
| 6 | 1 |
| 7 | 4 |
| 8 | 14 |
| 9 | 32 |
| 10 | 1 |
| 11 | 5 |
| 12 | 20 |
| 13 | 55 |
| 14 | 140 |
| 15 | 1 |
| 16 | 6 |
| 17 | 27 |
| 18 | 86 |
| 19 | 243 |
| 20 | 630 |
| 21 | 1 |
| 22 | 7 |
| 23 | 35 |
| 24 | 126 |
| 25 | 392 |
| 26 | 1099 |
| 27 | 2870 |
| 28 | 1 |
| 29 | 8 |
| 30 | 44 |
| 31 | 176 |
| 32 | 598 |
| 33 | 1808 |
| 34 | 5048 |
| 35 | 13256 |
| 36 | 1 |
| 37 | 9 |
| 38 | 54 |
| 39 | 237 |
| 40 | 873 |
| 41 | 2835 |
| 42 | 8433 |
| 43 | 23454 |
| 44 | 61389 |
| 45 | 1 |
| 46 | 10 |
| 47 | 65 |
| 48 | 310 |
| 49 | 1230 |
| 50 | 4272 |
| 51 | 13495 |
| 52 | 39640 |
| 53 | 109400 |
| 54 | 286710 |
| 55 | 1 |
| 56 | 11 |
| 57 | 77 |
[1,1,2,1,3,9,1,4,14,32,1,5,20,55,140,1,6,27,86, 243,630,1,7,35,126,392,1099,2870,1,8,44,176,598, 1808,5048,13256,1,9,54,237,873,2835,8433,23454, 61389,1,10,65,310,1230,4272,13495,39640,109400, 286710,1,11,77] |